Cam drive for managing disposable penetrating member actions with a single motor and motor and control system

ABSTRACT

An analyte and detecting apparatus has a housing and a disposable positionable in the housing. A penetrating member driver is positioned in the housing. A plurality of penetrating members are positioned in the disposable. Each a penetrating member is configured to be coupled to the penetrating member driver. A plurality of sampling chambers are provided with each one including an analyte sensor. A cam disk indexing and drive mechanism is included.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Ser. No. 61/148,767, which application is fully incorporated herein by reference.

BACKGROUND

1. Field of the Invention

This invention relates to analyte measurement devices, and more specifically, to systems and methods that securely hold a cam disk without the use of more complex non-back drivable gears.

2. Description of the Related Art

Lancing devices are known in the medical health-care products industry for piercing the skin to produce blood for analysis. Typically, a drop of blood for this type of analysis is obtained by making a small incision in the fingertip, creating a small wound, which generates a small blood droplet on the surface of the skin.

Early methods of lancing included piercing or slicing the skin with a needle or razor. Current methods utilize lancing devices that contain a multitude of spring, cam and mass actuators to drive the lancet. These include cantilever springs, diaphragms, coil springs, as well as gravity plumbs used to drive the lancet. The device may be held against the skin and mechanically triggered to ballistically launch the lancet. Unfortunately, the pain associated with each lancing event using known technology discourages patients from testing. In addition to vibratory stimulation of the skin as the driver impacts the end of a launcher stop, known spring based devices have the possibility of firing lancets that harmonically oscillate against the patient tissue, causing multiple strikes due to recoil. This recoil and multiple strikes of the lancet is one major impediment to patient compliance with a structured glucose monitoring regime.

Success rate generally encompasses the probability of producing a blood sample with one lancing action, which is sufficient in volume to perform the desired analytical test. The blood may appear spontaneously at the surface of the skin, or may be “milked” from the wound. Milking generally involves pressing the side of the digit, or in proximity of the wound to express the blood to the surface. In traditional methods, the blood droplet produced by the lancing action must reach the surface of the skin to be viable for testing.

When using existing methods, blood often flows from the cut blood vessels but is then trapped below the surface of the skin, forming a hematoma. In other instances, a wound is created, but no blood flows from the wound. In either case, the lancing process cannot be combined with the sample acquisition and testing step. Spontaneous blood droplet generation with current mechanical launching system varies between launcher types but on average it is about 50% of lancet strikes, which would be spontaneous. Otherwise milking is required to yield blood. Mechanical launchers are unlikely to provide the means for integrated sample acquisition and testing if one out of every two strikes does not yield a spontaneous blood sample.

Many diabetic patients (insulin dependent) are required to self-test for blood glucose levels five to six times daily. The large number of steps required in traditional methods of glucose testing ranging from lancing, to milking of blood, applying blood to the test strip, and getting the measurements from the test strip discourages many diabetic patients from testing their blood glucose levels as often as recommended. Tight control of plasma glucose through frequent testing is therefore mandatory for disease management. The pain associated with each lancing event further discourages patients from testing. Additionally, the wound channel left on the patient by known systems may also be of a size that discourages those who are active with their hands or who are worried about healing of those wound channels from testing their glucose levels.

Another problem frequently encountered by patients who must use lancing equipment to obtain and analyze blood samples is the amount of manual dexterity and hand-eye coordination required to properly operate the lancing and sample testing equipment due to retinopathies and neuropathies particularly, severe in elderly diabetic patients. For those patients, operating existing lancet and sample testing equipment can be a challenge. Once a blood droplet is created, that droplet must then be guided into a receiving channel of a small test strip or the like. If the sample placement on the strip is unsuccessful, repetition of the entire procedure including re-lancing the skin to obtain a new blood droplet is necessary.

Early methods of using test strips required a relatively substantial volume of blood to obtain an accurate glucose measurement. This large blood requirement made the monitoring experience a painful one for the user since the user may need to lance deeper than comfortable to obtain sufficient blood generation. Alternatively, if insufficient blood is spontaneously generated, the user may need to “milk” the wound to squeeze enough blood to the skin surface. Neither method is desirable as they take additional user effort and may be painful. The discomfort and inconvenience associated with such lancing events may deter a user from testing their blood glucose levels in a rigorous manner sufficient to control their diabetes.

A further impediment to patient compliance is the amount of time that at lower volumes, it becomes even more important that blood or other fluid sample be directed to a measurement device without being wasted or spilled along the way. Known devices do not effectively handle the low sample volumes in an efficient manner. Accordingly, improved sensing devices are desired to increase user compliance and reduce the hurdles associated with analyte measurement.

A further concern is the use of blood glucose monitoring devices in a professional setting. For the professional health care market, single device multiple user is the norm. A sterility barrier between patients is required or a single use professional lancing device is used and then discarded after use. To interface an integrated point of care lancing, sampling and analyte detection device with a multiple user paradigm, each lancet analyte detecting member pair may be isolated from the previous and subsequent user.

There is a need for an analyte measurement device with an improved disk indexing and drive mechanism. There is a further need for an analyte measurement device that employs a cam drive with a motion profile that is variable in real time to vary force, distance, speed, acceleration, noise levels and isolates cam-follower functions. There is a further need for an analyte measurement device with a cam disk motion profile where all movements are provided by a single motor and control system in order to significantly reduce parts, power and complexity.

SUMMARY

An object of the present invention is to provide an analyte measurement device that has an improved disk indexing and drive mechanism.

An further object of the present invention is to provide an analyte measurement device that has a cam drive with a motion profile that is variable in real time to vary force, distance, speed, acceleration, noise levels and isolates cam-follower functions.

Another object of the present invention is to provide an analyte measurement device with a cam disk motion profile where all movements are provided by a single motor and control system in order to significantly reduce parts, power and complexity.

These and other objects of the present invention are achieved in an analyte and detecting apparatus with a housing and a disposable positionable in the housing. A penetrating member driver is positioned in the housing. A plurality of penetrating members are positioned in the disposable. Each a penetrating member is configured to be coupled to the penetrating member driver. A plurality of sampling chambers are provided with each one including an analyte sensor. A cam disk indexing and drive mechanism is included.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates one embodiment of an analyte measurement apparatus of the present invention with a cam disk indexing and drive mechanism.

FIG. 2 illustrates another embodiment of an analyte measurement apparatus of the present invention with a cam disk indexing and drive mechanism that includes a battery, plate upper, PCB assembly, cam disk, plate lower, bobbin ear and a lancing disk.

FIG. 3 illustrates an embodiment of an analyte measurement apparatus of the present invention with a cam disk indexing and drive mechanism that has features selected from at least one of, indexing in variable increments, punch follower, indexing in an opposite direction, gripping of the penetrating member as well as un-gripping, park and un-park which is retaining and releasing of the gripper shaft and multiple punching.

FIG. 4 is a flow chart illustrating in one embodiment of operation of a cam disk indexing and drive mechanism of the present invention.

FIG. 5 illustrates one embodiment of a ratchet modeling of the present invention with two cams.

FIG. 6 illustrates one embodiment of a flowchart showing how a cam disk indexing and drive mechanism of the present invention operates.

As shown in FIG. 7 illustrates the operation of the indexer. A ratchet pushes a post on the indexer in one direction. An adjustment of indexing can be achieved to a selected active chamber.

FIG. 8 illustrates one embodiment of the present invention showing timing and angles of a cam disk.

DETAILED DESCRIPTION

In one embodiment of the present invention, an improved cam disk indexing and drive mechanism is provided. The present invention is particularly suitable with the analyte measurement and detecting systems disclosed in W.O. 2005/120365, incorporated herein by reference. In one embodiment, the cam disk manages all disposable penetrating member actions with a single motor drive, including but not limited to indexing, punching of one or more seals, and gripping of the penetrating member.

In one embodiment, a parking lever is provided that can include an over-molded rod, that can be made of a variety of materials including but not limited to carbon and the like. The over-molded rod is securely, safely and reliably constrained during inactivity of a penetrating member by a simple and single rotating cam feature contained within the single cam disk which is held securely without the use of more complex non-back drivable gears. In one embodiment, a pre-described cam disk motion profile is variable in real time to vary force, distance, speed, acceleration, noise levels and isolate cam-follower functions. All movements can be provided by a single motor and control system significantly reducing parts, power, complexity. A low precision low resolution cam disk can be provided that drives a high precision, high resolution penetrating member disposable and provides significant force, reliability, simplicity and accuracy benefits.

In various embodiments of the present invention, (i) rapid penetrating member cartridge foil detection mapping is achieved with multiple foil detection sensors in parallel or serial use, bi-directional ratcheted indexing movement, (ii) progressive real time foil detection of the in-use chamber ensures a foiled chamber is tested immediately prior to use, increasing safety and reliability, (iii) the cam disk enables seal (foil) detection without additional obligations of punching(s), gripping, or shield insertion which significantly reduces foil and penetrating member loss, (iv) cam disk ratchets and bi-directional drive enable isolate cam-follower functions out of sequence(s) such as independent penetrating member cartridge rotation without progressing sequential or previous cam disk followers, (v) the cam drive significantly simplifies complex and reliable mechanical movements in the handling and preparation of disposable objects, and (vi) an improved hub provides simple positive tactile insertion in any penetrating member cartridge chamber rotational orientation.

In FIG. 1, the cam drive 10 followers are illustrated. It includes the cam drive 10 and the disposable 14 that contains the penetrating members and glucose sensors. A gear box 16 and motor 18 are provided, which are the drive train for the cam disk 20. The cam includes a plurality of followers. The present invention provides a great deal of precision. Because there is a gear box, the driving system does not require accuracy. Repeatability is achieved because of the cam disk which has multiple operations and features on it. This activates a plurality of functions in the device. This provides a great economy of scale. Everything can be amplified to the disposable without much power. Large forces and speeds can be attained. Very rapid detection of the seals (foils) can be obtained with the present invention.

In this embodiment, the indexing and drive mechanism includes an actuator 21, disk cam module 22, lower/upper plate 24, parking lever 26, disk cam 28, punching lever 30, slide cam 32, outset mold 34, bobbin gear 36, indexing gear 38 and a center guide 50.

Additional elements of the FIG. 1 embodiment are illustrated in FIG. 2. As shown in FIG. 2, the indexing and drive mechanism includes a battery 42, plate upper 44, PCB assembly 46, cam disk 48, plate lower 50, bobbin ear 52 and a lancing disk 54. FIG. 2 shows a rigid chassis for the elements of the cam drive. A rigid structure is created by two plates and four posts.

FIG. 3 illustrates a cam drive with different features including but not limited to, indexing in variable increments, punch follower, indexing in an opposite direction, gripping of the penetrating member as well as un-gripping, park and un-park which is retaining and releasing of the gripper shaft, multiple punching, and the like.

FIG. 4 is a flow chart illustrating how the cam disk operates. By way of illustrating, indexing can proceed in two directions, and nested loops can be achieved. This programs a great number of sub-routines that can be performed.

FIG. 5 shows one embodiment of ratchet modeling of the present invention with two cams 56 and 58 that can be used with the present invention, index cam-1 and an index cam-2. These are then coupled to followers. The followers provide for indexing, punching, parking and gripping. All of these functions can occur at the same time. Additionally, with the present invention, a very repeatable process can be achieved.

In FIG. 6, illustrates a flowchart of how the cam disk can be operated. In this embodiment, the user starts with a test. The disposable seal is then taken into consideration. Indexing occurs at the punching station and then it is moved over to a gripping position. Right before the penetrating member is launched, it is parked. It is also parked after launch.

As shown in FIG. 7 the operation of the indexer is illustrated. A ratchet pushes a post on the indexer in one direction. An adjustment of indexing can be achieved to a selected active chamber.

FIG. 8 illustrates timing and angles of the cam disk. The cam disk can be moved in both x-y, and y-z directions. This provides for movement in three orthogonal directions. In FIG. 8, the first column lists follower functions, the second column lists motions, the third column lists the angle that the motion occurs in, the fourth column lists the number of gear teeth and the fifth column lists the time required.

Expected variations or differences in the results are contemplated in accordance with the objects and practices of the present invention. It is intended, therefore, that the invention be defined by the scope of the claims which follow and that such claims be interpreted as broadly as is reasonable. 

1. An analyte and detecting apparatus, comprising: a housing; a disposable positionable in the housing; a penetrating member driver positioned in the housing; a plurality of penetrating members positioned in the disposable and each of a penetrating member being configured to be coupled to the penetrating member driver; a plurality of sampling chambers each including an analyte sensor, each of a sampling chamber associated with a penetrating member; and a cam disk indexing and drive mechanism.
 2. The apparatus of claim 1, wherein the cam disk indexing and drive mechanism provides for management of penetrating member actions with a single motor drive.
 3. The apparatus of claim 2, wherein the penetrating member actions are selected from at least one of indexing and gripping of a penetrating member by the penetrating member driver.
 4. The apparatus of claim 1, further including: at least one seal associated with a penetrating member.
 5. The apparatus of claim 4, wherein the cam disk indexing and drive mechanism is configured to assist in punching the at least one seal prior to launch of a penetrating member.
 6. The apparatus of claim 1, further comprising: a parking lever.
 7. The apparatus of claim 6, wherein the parking lever includes an over-molded rod.
 8. The apparatus of claim 7, wherein the over-molded rod is constrained during inactivity of a penetrating member.
 9. The apparatus of claim 8, wherein the over-molded rod is constrained by a rotating cam feature provided by the cam disk indexing and drive mechanism.
 10. The apparatus of claim 1, wherein a cam disk indexing and drive mechanism motion profile is variable in real time.
 11. The apparatus of claim 1, wherein the cam disk indexing and drive mechanism movements are controlled by a single motor and control system.
 12. The apparatus of claim 1, further comprising: one or more seal detection mapping sensors.
 13. The apparatus of claim 1, wherein the cam disk indexing and drive mechanism is configured to provide seal detection without at least one of, punching, gripping and shield insertion.
 14. The apparatus of claim 1, wherein the cam disk indexing and drive mechanism is configured to provide a ratchet and bi-directional drive.
 15. The apparatus of claim 1, wherein the cam disk indexing and drive mechanism is configured to isolate cam-follower functions out of sequence.
 16. The apparatus of claim 1, wherein the cam disk indexing and drive mechanism includes a cam drive and a plurality of followers.
 17. The apparatus of claim 16, wherein the cam disk indexing and drive mechanism includes a gear box.
 18. The apparatus of claim 1, wherein the cam indexing and drive mechanism includes at least one of, an actuator, disk cam module, lower/upper plate, parking lever, disk cam, punching lever, slide cam, outset mold, bobbin gear, indexing gear and a center guide.
 19. The apparatus of claim 1, wherein the cam indexing and drive mechanism includes at least one of a, battery, plate upper, PCB assembly, cam disk, plate lower, bobbin ear and a lancing disk.
 20. The apparatus of claim 1, further comprising: a rigid chassis coupled to the cam indexing and drive mechanism.
 21. The apparatus of claim 1, wherein the cam indexing and drive mechanism includes functions selected from at least one of, indexing in variable increments, punch follower, indexing in an opposite direction, gripping and un-gripping of a penetrating member, retaining and releasing of a gripper shaft configured to be coupled to the penetrating member drive and punching of one or more seals.
 22. The apparatus of claim 1, wherein the cam indexing and drive mechanism provides for indexing in first and second opposing directions.
 23. The apparatus of claim 1, wherein the cam indexing and drive mechanism includes first and second cams.
 24. The apparatus of claim 1, wherein the cam indexing and drive mechanism initiates indexing at a punching station and a gripping member then grips a penetrating member prior to launch of a penetrating member. 